历元，在天文学是一些天文变数作为参考的时刻点，例如天球座标或天体的椭圆轨道要素，因为这些会受到摄动而随着时间变化。这些会随着时间变动的天文变量可能包括天体的平黄经或平近点角、轨道相对于参考平面的交点、轨道近日点和远日点或拱点的方向、其轨道半长轴的大小等等。
双语例句原声例句
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提出了一种基于双频观测数据的单历元周跳探测和修复方法。
A new method is proposed for detecting and repairing cycle slips in GPS navigation based on the dual frequency observations.
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提出相邻历元间差分算法，大大简化了观测方程，同时避免积分常量的计算。
A differential arithmetic is proposed for simplifying the observational equation as well as for avoiding the computation of the unknown integer constant.
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其次，研究了历元状态滤波算法，分析其工作原理，并推导出了状态方程和测量方程。
Secondly, epoch state filter is studied by analyzing its working principle and deriving the state equation and measurement equation.
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I shouldn't say list, those two tuples, and walk through them to find the pieces that match up.
除数数组进行对比，我不该说数组的，是元组,遍历这两个元组找到相同的元素。
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$firstVoiceSent
- 来自原声例句